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Advancement in FET technology has forced researchers to seek alternate semiconductor devices and materials. TFETs, junctionless FETs, and nanowires are a few examples of modern FETs, whereas Si alloys, graphene, and TMDC are a few materials that have shown promising behaviour to replace Si in the future. In this work, SiGeC/SiGe/SiC–Si based vertical heterostructure nanowires have been investigated. Due to the nanoscale dimensions of the FET and to incorporate the quantum effects along with Schrodinger-Poisson equations, non-equilibrium Green's function has been used as a principle simulator. For simulation, Ge/Carbon mole concentration of 0.25 and 0.01, respectively is used. To thoroughly investigate the effect of variation in doping profile and temperature range, simulated heterojunction nanowire showed that SiGeC-based nanowire result in a better I ON /I OFF ratio as compared to SiGe and SiC-based heterojunction nanowire. • Novel SiGeC-Si heterojunction material based vertical nanowire FET has been investigated. • Along with non-equillibrium Green's function, Schrodinger-Poisson's equation is used as principle simulator. • Results are discussed in terms of transmission, density of states at the source and the drain electrode. • Effect of variation in doping and temperature on the properties of SiGeC and the vertical nanowire has been explained. • Comparison of SiGeC-Si, SiGe-Si, and SiC–Si heterojunction shows that SiGeC results in better properties then the other Si-composites. [ABSTRACT FROM AUTHOR]

Background: Class 1C antiarrhythmic drugs (AAD) have been associated with harm in patients treated for ventricular arrhythmias with a prior myocardial infarction. Consensus guidelines have advocated that these drugs not be used in patients with stable coronary artery disease (CAD). However, long-term data are lacking to know if unique risks exist when these drugs are used for atrial fibrillation (AF) in patients with CAD without a prior myocardial infarction.Methods: In 24,315 patients treated with the initiation of AADs, two populations were evaluated: (1) propensity-matched AF patients with CAD were created based upon AAD class (flecainide, n = 1,114, vs class-3 AAD, n = 1,114) and (2) AF patients who had undergone a percutaneous coronary intervention or coronary artery bypass graft (flecainide, n = 150, and class-3 AAD, n = 1,453). Outcomes at 3 years for mortality, heart failure (HF) hospitalization, ventricular tachycardia (VT), and MACE were compared between the groups.Results: At 3 years, mortality (9.1% vs 19.3%, P < .0001), HF hospitalization (12.5% vs 18.3%, P < .0001), MACE (22.9% vs 36.6%, P < .0001), and VT (5.8% vs 8.5%, P = .02) rates were significantly lower in the flecainide group for population 1. In population 2, adverse event rates were also lower, although not significantly, in the flecainide compared to the class-3 AAD group for mortality (20.9% vs 25.8%, P = .26), HF hospitalization (24.5% vs 26.1%, P = .73), VT (10.9% vs 14.7%, P = .28) and MACE (44.5% vs 49.5%, P = .32).Conclusions: Flecainide in select patients with stable CAD for AF has a favorable safety profile compared to class-3 AADs. These data suggest the need for prospective trials of flecainide in AF patients with CAD to determine if the current guideline-recommended exclusion is warranted. [ABSTRACT FROM AUTHOR]

Background: postoperative atrial fibrillation (POAF) is a common cardiac surgery complication that is associated with increased complications and negative outcomes, but the association between presurgical atrial conduction abnormalities and POAF has not been investigated clinically during premature atrial S1S2 stimulation. This clinical study sought to examine whether intraoperative premature atrial stimulation reveals increased areas of slowed and/or blocked conduction in patients that develop POAF.Methods: High-density intraoperative epicardial left atrial mapping was conducted in 20 cardiac surgery patients with no prior history of atrial fibrillation (AF). In 20 patients, 6 (30%) developed POAF. A flexible-array of 240-electrodes was placed on the posterior left atrial wall in between the pulmonary veins. Activation maps were generated for sinus and premature atrial S1S2 stimulated beats. The area of conduction block (CB), conduction delay (CD) and the combination of both (CDCB) for conduction velocity < 0.1, 0.1 ≤ x < 0.2 and < 0.2 m/s, respectively were quantified.Results: For a premature atrial S2 beat with shortest cycle length captured, conduction velocity maps revealed a significantly higher area for CD (13.19 ± 6.59 versus 6.06 ± 4.22 mm2, p = 0.028) and CDCB (17.36 ± 8.75 versus 7.41 ± 6.39 mm2, p = 0.034), and a trend toward a larger area for CB (4.17 ± 3.66 versus 1.34 ± 2.86 mm2, p = 0.063) in patients who developed POAF in comparison to those that remained in the sinus. Sinus and S1 paced beats did not show substantial differences in abnormal conduction areas between patients with and without POAF.Conclusion: In comparison to sinus and S1 beats, premature atrial S2 beats accentuate conduction abnormalities in the posterior left atrial wall of cardiac surgery patients that developed POAF. [ABSTRACT FROM AUTHOR]

Effect of carbon concentration of parent austenite on isothermal transformation to bainite has been studied. It has been shown that when the carbon concentration of parent austenite is low and the transformation temperature is higher than the Zener ordering temperature, the carbon content of bainitic ferrite is low. On the other hand, it is unusually high when parent austenite has higher carbon and the transformation temperature is less than the Zener ordering temperature. The results have been rationalised on the basis of Zener ordering of carbon atoms resulting in the formation of BCT ferrite with higher solubility of carbon. Similarly, the carbon content of untransformed austenite in the former case was found to closely follow the T 0 curve line whereas it was higher than T 0 in the latter case. A theoretical framework based on the equilibrium between BCT ferrite and austenite has been proposed to explain the shift of the T 0 curve to higher carbon concentration. Finally, the revised limits of carbon concentration of bainitic ferrite and austenite have been suggested for the calculation of the relative fractions of these phases when transformation temperature is less than the Zener ordering temperature. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Background: Antitachycardia pacing (ATP) success rates as low as 50% for fast ventricular tachycardias (VTs) have been reported providing an opportunity for improved ATP to decrease shocks.Objective: The purpose of this study was to determine how a new automated antitachycardia pacing (AATP) therapy would perform compared with traditional burst ATP using computer modeling to conduct a virtual study.Methods: Virtual patient scenarios were constructed from magnetic resonance imaging and electrophysiological (EP) data. Cardiac EP simulation software (CARPEntry) was used to generate reentrant VT. Simulated VT exit sites were physician adjudicated against corresponding clinical 12-lead electrocardiograms. Burst ATP comprised 3 sequences of 8 pulses at 88% of VT cycle length, with each sequence decremented by 10 ms. AATP was limited to 3 sequences, with each sequence learning from the previous sequences.Results: Two hundred fifty-nine unique ATP scenarios were generated from 7 unique scarred hearts. Burst ATP terminated 145 of 259 VTs (56%) and accelerated 2.0%. AATP terminated 189 of 259 VTs (73%) with the same acceleration rate. The 2 dominant ATP failure mechanisms were identified as (1) insufficient prematurity to close the excitable gap; and (2) failure to reach the critical isthmus of the VT. AATP reduced failures in these categories from 101 to 63 (44% reduction) without increasing acceleration.Conclusion: AATP successfully adapted ATP sequences to terminate VT episodes that burst ATP failed to terminate. AATP was successful with complex scar geometries and EP heterogeneity as seen in the real world. [ABSTRACT FROM AUTHOR]

Postoperative atrial fibrillation (POAF) after cardiac surgery remains a highly prevalent and costly condition that negatively impacts patient quality of life and survival. Numerous retrospective studies, meta-analysis, and review papers have been reported identifying POAF risk based on patients' risk factors and clinical biomarkers. In this narrative review, the authors report significant variations among selected pre- and perioperative biomarkers used to predict POAF incidence in patients without a history of atrial fibrillation (AF). POAF prediction based on B-type natriuretic peptide, N-terminal pro B-type natriuretic peptide, C-reactive protein, interleukin-6, creatinine, and plasminogen activator inhibitor-1 differs significantly among different studies, thereby limiting their clinical utility to predict POAF risk with high accuracy. Conversely, soluble vascular endothelial cells adhesion molecule-1, soluble CD40 ligand, Galectin-3, and aldosterone show promise for better POAF prediction. However, the current datasets for these selected biomarkers are not of sufficient size to validate the broad clinical application specifically for patients with no prior history of AF. [ABSTRACT FROM AUTHOR]

Abstract Esterases are an important group of biocatalysts for synthetic organic chemistry. Functional metagenomics allows discovery of novel biocatalysts by providing access to the gene pool of the microbial community of a habitat. Two metagenomic libraries representing the gene pool of sea sediment and hot spring microbial mat were constructed. Functional screening of these libraries resulted in the isolation of total 8 clones with tributyrin hydrolytic activity. Sequence analysis revealed 10 putative lipolytic proteins with 42–99% homology to the protein sequences in the databases, nine of which represented six known esterase families. Four of the encoded proteins represented Family V and amongst others, one each represented the Family VIII, pectin acetylesterase, enterobactin esterase, G-D-S-L family and OsmC domain containing esterase. One unusual lipolytic protein possessed poly-(3-hydroxybutyrate) depolymerase domain fused to lipase/esterase domain. Two phylogenetically related esterases (MLC3 and SLC5) belonging to family V were expressed and purified to homogeneity. The enzymes exhibited environment-adapted temperature optimum and thermostability. MLC3 was able to stereoselectively hydrolyze R-methyl mandelate to produce R-mandelic acid, an important chiral building block, which suggests MLC3 has potential commercial application. [ABSTRACT FROM AUTHOR]

Background: Differentiating between atrial fibrillation (AF) and atrial tachycardia (AT) or atrial flutter (AFL) on surface ECG can be challenging. The same problem arises in animal models of AF, in which atrial arrhythmias are induced by pacing or pharmacological intervention with the goal of making mechanistic determinations. Some of these induced arrhythmias can be AFL or AT, even though it might appear as AF on the body-surface ECG based on irregular R-R intervals. We hypothesize that a dominant frequency (DF) analysis of the ECG can differentiate between the two distinct arrhythmias, even when it is not evident by the presence of flutter waves or beat-to-beat regularity when looking at brief recordings.Methods: Canine model (n = 15, 10 controls and 5 Persistent AF animals with >6 months of AF) was used to test the hypothesis. Atrial arrhythmia was induced by rapid atrial pacing. Five blinded observers evaluated the 3‑lead surface ECGs recorded during atrial arrhythmia and classified the rhythm as AFL/AT or AF. The 64-electrode Constellation (Boston Scientific) catheter was used to acquire left (entire group) and right (7 of 10 controls) atrial intracardiac electrograms. For the surface ECG and the intracardiac electrograms, Welch method with a hamming window and 50% overlap was used to calculate DF of two-minute segments. Mean of standard deviations of the DF values were calculated for both ECGs and intracardiac EGMs. Ground truth came from activations maps and DF analysis derived from the intracardiac electrograms recorded in the two chambers.Results: Rapid pacing induced atrial arrhythmias in all the control animals. The ECG in 8 of the 10 control cases was read as AF by at least 80% percent of observers even though the EGMs from the Constellation showed organized activation and consistent DF (STD of DF < 0.001) in all the electrodes confirming the arrhythmia as AFL in 10/10 cases. In the persistent AF group, the DF from the three lead ECGs were significantly different (Mean of STDs = 2.65 ± 0.99) whereas the DF in the control animals with AFL was consistent across all ECG channels (Mean of STDs < 0.001), and the DF in the control animals ECGs was in agreement with the DF of the intracardiac electrograms.Conclusion: Surface ECG recordings can mimic AF even when the underlying atrial arrhythmia is AFL in control canine models. DF variation of the signals from multiple surface ECG leads can help differentiate between the AF and AFL. [ABSTRACT FROM AUTHOR]

In this manuscript, a novel semiconductor device termed an extended source F-type nano field effect transistor is proposed. The low bandgap material used at the source electrode is extended up to the drain electrode. At the drain electrode, extended material is confined by wide bandgap material to reduce the OFF-State current. For simulation, Schrodinger-Poisson equations are used to construct the Hamiltonian and non-equilibrium Green's function is used to evaluate the transport. For a thorough analysis, various materials are considered at source and drain electrodes. After investigation, the device is proposed with Si 0.45 Ge 0.55 at the source electrode and SiC as confining material. The proposed device resulted in I OFF = 3.6 × 10−14 A/μm and I ON = 8.27 × 10−4 A/μm. I DS -V GS characteristics are justified on basis of energy curve, transmission probability, and density of states at source and drain terminal. For the entire combination, device resulted in a subthreshold slope of approximately 60mV/dec. The proposed device can be used in the future to replace current field-effect transistors as it results in better characteristics than metal oxide semiconductor field effect transistors and will have a much simpler fabrication process than tunnel field-effect transistors. • A novel semiconductor device termed an extended source F-type nano field effect transistor is proposed with Si 1-x Ge x –WBG heterostructure to improve the analog performance. • For simulation, Schrodinger-Poisson equations are used to construct the Hamiltonian and non-equilibrium green's function is used to evaluate the transport mechanism of the device. • To enrich the electrostatic control, a dual gate (both gates are common) configuration has been employed. • The proposed device can be used in the future to replace current field-effect transistors as it results in better characteristics than MOSFET and will have a much simpler fabrication process than TFET. [ABSTRACT FROM AUTHOR]

Artificial intelligence (AI) innovation in healthcare has emerged as an increasingly significant area of research. AI, digital data collection, and computer infrastructure advancements have empowered humans to address complex healthcare challenges. This study conducts a systematic literature review (SLR) of peer-reviewed journal articles at the intersection of AI, innovation, and healthcare to offer research directions for scholars and leaders in healthcare management. To achieve this, the systematic review identified and analyzed 378 published studies on AI innovation in healthcare. Evaluating these publications based on inclusion and exclusion criteria yielded 75 studies ultimately selected for comprehensive analysis. This research adds to the scope of previous investigations by aiming to 1) emphasize the most crucial AI-based healthcare applications, 2) explore challenges associated with AI integration in healthcare, and 3) examine student adoption and incorporation of AI into existing healthcare curricula. We also conducted an exploratory study of over 2700 AI-enabled healthcare startups worldwide to supplement our literature review. The SLR reveals several gaps within the research scope and proposes corresponding future research directions. These future research directions will assist researchers and enable healthcare professionals to develop legislation that accelerates the adoption of AI solutions in healthcare, ultimately enhancing public access to efficient and effective healthcare services. • Artificial intelligence (AI) innovation in healthcare is an area of increasing interest. • This research expands on previous work by examining AI healthcare apps, their integration obstacles, and student adoption. • The study explores 2,747 AI-enabled healthcare startups worldwide, providing insights into AI innovation in healthcare. • There is a limited amount of research that has been conducted on startups in the field of AI healthcare. [ABSTRACT FROM AUTHOR]

Steady state analysis of GeSn alloy based single quantum well mid-infrared transistor lasers (TL) is reported in this paper. A theoretical model for the device is developed by considering the active Ge 0.85 Sn 0.15 well in the base of the transistor. The Model includes the effect of strain on the material gain and free carrier absorption in the active layer and optical confinement factor in various layers of the device. Laser rate equation and continuity equation for bulk minority carrier with 2-D carrier distribution in the active layer are solved to obtain the threshold base current density and other steady-state parameters of the device like photon density, current gain, etc. Results show that Sn composition in the active GeSn layer and some device parameters play important roles in the performance of the device. An estimated threshold base current density of 2.6 kA/cm 2 with the current gain of 2722 is obtained for a particular composition of Sn into SiGeSn/GeSn alloy in the base. [ABSTRACT FROM AUTHOR]

G protein-coupled receptors (GPCRs) are major signal recognition and transmission units in the plasma membrane. The interaction of activated and phosphorylated GPCRs with the multifunctional adaptor proteins β-arrestins (βarrs) is crucial for regulation of their signaling and functional outcomes. Over the past few years, a range of structural, biochemical, and cellular studies have revealed novel insights into GPCR–βarr interaction and signaling. Some of these findings have come as a surprise and therefore have the potential to significantly refine the conceptual framework of the GPCR–βarr system. Here we discuss these recent advances with particular emphasis on biphasic GPCR–βarr interaction, the formation of GPCR–G-protein–βarr supercomplexes, and receptor-specific conformational signatures in βarrs. We also underline the emerging research areas that are likely to be at the center stage of investigations in the coming years. [ABSTRACT FROM AUTHOR]

Recent studies have established that a complex community of microbes colonize the human urinary tract; however, their role in kidney transplant patients treated with prophylactic antibiotics remains poorly investigated. Our aim was to investigate the urinary microbiome of kidney transplant recipients. Urine samples from 21 patients after kidney transplantation and 8 healthy controls were collected. All patients received prophylactic treatment with the antibiotic combination trimethoprim-sulfamethoxazole. Metagenomic DNA was isolated from urine samples, sequenced using shotgun sequencing approach on Illumina HiSeq 2000 platform, and analyzed for microbial taxonomic and functional annotations. Our results demonstrate that the urine microbiome of kidney transplants was markedly different at all taxonomic levels from phyla to species, had decreased microbial diversity, and increased abundance of potentially pathogenic species compared with healthy controls. Specifically, at the phylum level, we detected a significant decrease in Actinobacteria and increase in Firmicutes due to increases in Enterococcus faecalis. In addition, there was an increase in the Proteobacteria due to increases in Escherichia coli. Analysis of predicted functions of the urinary metagenome revealed increased abundance of enzymes in the folate pathway including dihydrofolate synthase that are not inhibited by trimethoprim-sulfamethoxazole, but can augment folate metabolism. This report characterizes the urinary microbiome of kidney transplants using shotgun metagenomics approach. Our results indicate that the urinary microbiota may be modified in the context of prophylactic antibiotics, indicating that a therapeutic intervention may shift the urinary microbiota to select bacterial species with increased resistance to antibiotics. The evaluation and development of optimal prophylactic regimens that do not promote antibiotic resistance is an important future goal. [ABSTRACT FROM AUTHOR]